Gummy Smiles: The Importance of a Correct Diagnosis

This young girl (Figure 1) was about to start college and expressed concerned about her smile. She did not like her teeth and was told she needed to veneer them. She came to us for a second opinion.

On examination, what jumped out at me was her gummy smile. She had an excessive gingival display that was approximately 5mm and central incisors that lacked prominence in her smile. We started exploring her gummy smile to get a diagnosis and formulate the right treatment plan.

We know that there are seven possible causes of a gummy smile:

1. Short upper lip
2. Hypermobile lip
3. Vertical maxillary excess (VME)
4. Anterior over eruption due to excessive overjet)
5. Wear and compensatory eruption
6. Altered active eruption
7. Altered passive eruption

We examined her upper lip which had normal length but was slightly hypermobile. She had 3mm of incisal edge display at rest which was appropriate and ruled out VME. Her anterior and posterior occlusal planes were level, which ruled out anterior over eruption and she had no incisal edge wear.

However she had short clinical crown height, which suggested possible altered eruption. On probing her periodontal pocket, under local anesthetic, we could not feel her CEJ. The periodontist evaluated her and determined she had altered active eruption. The crowns of the teeth failed to fully erupt out of the osseous housing, leaving the osseous crest level with the CEJ.

We recommended osseous crown lengthening from teeth 5-12 as well as tooth whitening and minor composites at incisal corners to correct for narrow incisal shape (Figure 2). 

Ultimately she was happy with the outcome of her smile and did not require veneers (Figure 3). If we had not made the correct diagnosis she could have potentially had the wrong treatment and been unhappy with the outcome. Patient satisfaction is always a main goal for dentists. 

So a correct diagnosis can give us more appropriate treatments and better outcome. Every time I see a patient I wonder if I am making the correct diagnosis. What also scares me is when I am the patient myself wondering if I am being correctly diagnosed and treated! This is a good example of how can change the shape of the tooth from Danny Devito teeth to George Clooney teeth. 

Arezoo Bahar, DDS, Visiting Faculty and Contributing Author